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    <title>mtlb_fftshift</title>
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    <center>M2SCI function</center>
    <div align="right">Last update : 28/07/2004</div>
    <p>
      <b>mtlb_fftshift</b> - Matlab fftshift emulation function</p>
    <h3>
      <font color="blue">Description</font>
    </h3>
    <p>Matlab and Scilab <tt>
        <b>fftshift</b>
      </tt> behave differently in some particular cases:</p>
    <dl>
      <dd>
        <b></b>
        <dd>
          <li>
            <b>
              <font color="maroon"></font>
            </b>
        With character string input: due to the fact that character strings are not considered in the same way in Matlab and Scilab, results can be different for this kind of input.
        </li>
          <li>
            <b>
              <font color="maroon"></font>
            </b>
        With two inputs: Matlab <tt>
              <b>fftshift</b>
            </tt> can work even if <tt>
              <b>dim</b>
            </tt> parameter is greater than number of dimensions of first input.
        </li>
        </dd>
      </dd>
    </dl>
    <p>
    The function <tt>
        <b>mtlb_fftshift(A[,dim])</b>
      </tt> is used by
    <tt>
        <b>mfile2sci</b>
      </tt> to replace <tt>
        <b>fftshift(A[,dim])</b>
      </tt> when it was not
    possible to know what were the inputs while porting Matlab code to Scilab. This function will
    determine the correct semantic at run time. If you want to have a
    more efficient code it is possible to replace <tt>
        <b>mtlb_fftshift</b>
      </tt> calls:
    </p>
    <dl>
      <dd>
        <b></b>
        <dd>
          <li>
            <b>
              <font color="maroon"></font>
            </b>
        If <tt>
              <b>A</b>
            </tt> is not a character string matrix,
        <tt>
              <b>mtlb_fftshift(A)</b>
            </tt> may be replaced by <tt>
              <b>fftshift(A)</b>
            </tt>
          </li>
          <li>
            <b>
              <font color="maroon"></font>
            </b>
         If <tt>
              <b>A</b>
            </tt> is not a character string matrix and <tt>
              <b>dim</b>
            </tt> is not greater than <tt>
              <b>size(size(a),"*")</b>
            </tt>,
        <tt>
              <b>mtlb_fftshift(A,dim)</b>
            </tt> may be replaced by <tt>
              <b>fftshift(A,dim)</b>
            </tt>
          </li>
        </dd>
      </dd>
    </dl>
    <p>Caution: <tt>
        <b>mtlb_fftshift</b>
      </tt> has not to be used for hand coded functions.</p>
    <h3>
      <font color="blue">Authors</font>
    </h3>
    <dl>
      <dd>
        <b></b>V.C.</dd>
    </dl>
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